The title is a bit of a misnomer. It is mostly about the kooky things people believe and why those beliefs are not true, not why people believe them. People believe in quantum mechanics and relativity, which are far weirder than any alien abduction or holocaust denial. That is not what the book is about. It about people believing in things for which there is almost no evidence and for which there is a ton of counter-evidence. It covers Holocaust denial and creationism in considerable detail and has chapters on abductions, Satanism, Afrocentrism, near-death experiences, Ayn Randian positivism and psychics. His five reasons people hold crank beliefs are:

for consolation

for immediate gratification

for simplicity

for moral meaning

because hope springs eternal

As a former fundamentalist Christian, he has first hand knowledge. He is also founder of the Skeptics Society.

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